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31.
Raloxifene, the prototype of the selective estrogen receptor modulators, has been associated with an increased risk of venous thromboembolism. As hemorheological factors may be involved in thrombus formation this placebo-controlled study investigated whether raloxifene was associated with changes in determinants of blood viscosity. Fifty-seven post-menopausal women were randomly assigned to receive placebo, raloxifene 60 mg/day, or raloxifene 120 mg/day for 36 months. Venous blood samples were collected at baseline and at 12-monthly intervals and used to measure hematocrit, whole blood and plasma viscosity and plasma fibrinogen concentration. Time- and treatment-related changes in the grouped and pooled data was analysed using ANOVA with repeated measures and correlation matrices. The mean values of all the hemorheological indices showed small inconsistent changes within the normal reference range over the 36-month period of the study. There was a small but significant decrease over time in high shear rate blood viscosity and plasma viscosity in raloxifene-treated subjects compared to those receiving placebo (p<0.05). Correlation analyses showed the anticipated relationships between blood viscosity and hematocrit and plasma viscosity levels and also between plasma viscosity and plasma fibrinogen concentration. No subject developed a thromboembolic vascular event during the study. These results show that compared with placebo treated-subjects, long-term raloxifene treatment in post-menopausal women, at a dose of either 60 or 120 mg daily, was not associated with adverse changes in hemorheological factors that may contribute to venous thromboembolism.  相似文献   
32.
Abstract

Adolescent mothers face problems that can lead to psychological stress. Based on prospective data from the present study, these problems point toward the need for a coping skills prevention approach to help adolescent mothers manage stress. This paper reports data from outcome research on such an approach with adolescent mothers. Subjects were 79 adolescent mothers who were tested before, immediately after, and three months following the provision of coping skills intervention in an experimental condition. Subjects in a test-only control condition received no special intervention. At posttest, experimental condition subjects showed more positive outcomes on measures of social support, cognitive performance, conflict management, and interpersonal competence. At three-month follow-up, experimental condition subjects had more positive outcomes on social support, cognitive performance, parenting ability, child care self-efficacy, and measures of psychological well-being.  相似文献   
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Urologic complications are the most frequent technical adverse events following kidney transplantation (KTX). We evaluated traditional and novel potential risk factors for urologic complications following KTX. Consecutive KTX recipients between December 1, 2006 and December 31, 2010 with at least six‐month follow‐up (n = 635) were evaluated for overall urologic complications accounting for donor, recipient, and transplant characteristics using univariate and multivariate logistic regression. Urologic complications occurred in 29 cases (4.6%) at a median of 40 d (range 1–999) post‐transplantation and included 17 ureteral strictures (2.6%), five (0.8%) ureteral obstructions due to donor‐derived stones or intraluminal thrombus, and seven urine leaks (1.1%). All except two complications occurred within the first year of transplantation. Risk factors for urologic complications on univariate analysis were dual KTX (p = 0.04) and renal artery multiplicity (p = 0.02). On multivariate analysis, only renal artery multiplicity remained significant (aHR 2.4, 95% confidence interval 1.1, 5.1, p = 0.02). Donation after cardiac death, non‐mandatory national share kidneys, donor peak serum creatinine > 1.5 mg/dL or creatinine phosphokinase > 1000 IU/L, and donor down time were not associated with urologic complications. Our data suggest that donor artery multiplicity is an independent risk factor for urologic complications following KTX.  相似文献   
35.
  • Left gastric artery embolization acutely lowers ghrelin levels and is associated with modest weight loss sustainable for 1 year in morbidly obese patients.
  • The procedure is relative quick, free of access complications when done via the radial artery, but long‐term sequelae and the durability of ischemic injury to the fundus of the stomach is uncertain.
  • Present reports provide pilot and proof‐of‐concept data that should fashion further study, but application to routine practice today is premature.
  相似文献   
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Platelet Endothelial Cell Adhesion Molecule 1 (PECAM-1) deficient mice in the FVB/n strain exhibit fatal chronic pulmonary fibrotic disease. The illness occurs in the absence of a detectable pro-inflammatory event. PECAM-1 is vital to the stability of vascular permeability, leukocyte extravasation, clotting of platelets, and clearance of apoptotic cells. We show here that the spontaneous development of fibrotic disease in PECAM-1 deficient FVB/n mice is characterized by early loss of vascular integrity in pulmonary capillaries, resulting in spontaneous microbleeds. Hemosiderin-positive macrophages were found in interstitial spaces and bronchoalveolar lavage (BAL) fluid in relatively healthy animals. We also observed a gradually increasing presence of hemosiderin-positive macrophages and fibrin deposition in the advanced stages of disease, corresponding to the accumulation of collagen, IL-10 expression, and myofibroblasts expressing alpha smooth muscle actin (SMA). Together with the growing evidence that pulmonary microbleeds and coagulation play an active part in human pulmonary fibrosis, this data further supports our hypothesis that PECAM-1 expression is necessary for vascular barrier function control and regulation of homeostasis specifically, in the pulmonary environment.  相似文献   
39.
In the ovarian follicle, oocyte-secreted factors induce cumulus-specific genes and repress mural granulosa cell specific genes to establish these functionally distinct cell lineages. The mechanism establishing this precise morphogenic pattern of oocyte signaling within the follicle is unknown. The present study investigated a role for heparan sulphate proteoglycans (HSPG) as coreceptors mediating oocyte secreted factor signaling. In vitro maturation of cumulus oocyte complexes in the presence of exogenous heparin, which antagonizes HSPG signaling, prevented cumulus expansion and blocked the induction of cumulus-specific matrix genes, Has2 and Tnfaip6, whereas conversely, the mural granulosa-specific genes, Lhcgr and Cyp11a1, were strongly up-regulated. Heparin also blocked phosphorylation of SMAD2. Exogenous growth differentiation factor (GDF)-9 reversed these heparin effects; furthermore, GDF9 strongly bound to heparin sepharose. These observations indicate that heparin binds endogenous GDF9 and disrupts interaction with heparan sulphate proteoglycan coreceptor(s), important for GDF9 signaling. The expression of candidate HSPG coreceptors, Syndecan 1-4, Glypican 1-6, and Betaglycan, was examined. An ovulatory dose of human chorionic gonadotropin down-regulated Betaglycan in cumulus cells, and this regulation required GDF9 activity; conversely, Betaglycan was significantly increased in luteinizing mural granulosa cells. Human chorionic gonadotropin caused very strong induction of Syndecan 1 and Syndecan 4 in mural granulosa as well as cumulus cells. Glypican 1 was selectively induced in cumulus cells, and this expression appeared dependent on GDF9 action. These data suggest that HSPG play an essential role in GDF9 signaling and are involved in the patterning of oocyte signaling and cumulus cell function in the periovulatory follicle.  相似文献   
40.
Composite orthopaedic coatings with antibacterial capability containing chitosan, Bioglass® particles (9.8 μm) and silver nanoparticles (Ag-np) were fabricated using a single-step electrophoretic deposition (EPD) technique, and their structural and preliminary in vitro bactericidal and cellular properties were investigated. Stainless steel 316 was used as a standard metallic orthopaedic substrate. The coatings were compared with EPD coatings of chitosan and chitosan/Bioglass®. The ability of chitosan as both a complexing and stabilizing agent was utilized to form uniformly deposited Ag-np. Due to the presence of Bioglass® particles, the coatings were bioactive in terms of forming carbonated hydroxyapatite in simulated body fluid (SBF). Less than 7 wt.% of the incorporated silver was released over the course of 28 days in SBF and the possibility of manipulating the release rate by varying the deposition order of coating layers was shown. The low released concentration of Ag ions (<2.5 ppm) was efficiently antibacterial against Staphyloccocus aureus up to 10 days. Although chitosan and chitosan/Bioglass® coating supported proliferation of MG-63 osteoblast-like cells up to 7 days of culture, chitosan/Bioglass®/Ag-np coatings containing 342 μg of Ag-np showed cytotoxic effects. This was attributed to the relatively high concentration of Ag-np incorporated in the coatings.  相似文献   
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